Determination of preservatives in food products by cyclodextrin-modified capillary electrophoresis with multiwavelength detection

Abstract

A high-performance capillary electrophoretic method with multiwavelength detection was developed to analyze frequently used preservatives. The effects of alpha-cyclodextrin and beta-cyclodextrin on migration behaviours of nine preservatives were investigated. The preservatives were successfully separated within 9 min using a borax-NaOH buffer (pH 10.0) modified with 2 mM alpha-cyclodextrin. In optimized separation conditions, the reproducibilities of the migration times of the preservatives were satisfactory (R.S.D. values <0.99%). The correlation coefficients of the linear calibration graphs for the preservatives, ranging between 5 and 500 mu g ml(-1), exceeded 0.991. By employing this reliable capillary electrophoresis method, preservatives in three different food products were determined.